Method of processing and packaging milk



Sept. 1968 R. P. OGDEN ETYAL 3,403,034

METHOD OF PROCESSING AND PACKAGING MILK Filed Jan. 9, 1967 INVENTORSRALPH F. OGDEN BY WILLIAM P. LAWSON ATTORNEYS United States Patent 03,403,034 METHOD OF PROCESSING AND PACKAGING MILK Ralph P. Ogden,Hammond, Ind. (19 Bender St., Park Forest, Ill. 60466), and William P.Lawson, 7522 Walnut St., Hammond, Ind. 46324 Continuation-impart ofapplication Ser. No. 507,623, Oct. 22, 1965, which is acontinuation-in-part of application Ser. No. 167,694, Jan. 22, 1962.This application Jan. 9, 1967, Ser. No. 608,122 The portion of the termof the patent subsequent to Jan. 10, 1984, has been disclaimed 2 Claims.(Cl. 99-200) ABSTRACT OF THE DISCLOSURE The disclosure pertains to amethod of processing and packaging milk which involves partiallyconcentrating the milk, flash freezing said milk to form a film of solidconcentrate, fragmenting the frozen film, compacting the solidconcentrate fragments into cakes, and packaging one or more of the cakesin a container.

This application is a continuation-in-part of our application Ser. No.507,623, filed Oct. 22, 1965, now Patent No. 3,297,455, granted Jan. 10,1967, which was a continuation-in-part of our abandoned application Ser.No. 167,694, filed Jan. 22, 1962.

Our invention relates to a method of freezing liquid products. The termliquid product as used herein includes slurries, emulsions, solutions,and mixtures which are susceptible to the method of the invention. Theinvention will be exemplified as applied to thoroughly mixed fresh wholemilk or to homogenized fresh whole milk to produce on an economicalbasis a dried milk product that in its reconstituted form is fully aspalatable as the original, or alternatively, a frozen whole milk productthat is adapted for ready packaging and wide distribution.

At the present time, the producing and marketing of milk is closely tiedin geographically with the location of its market area because of thehigh water content in milk and the consequent critical requirements forrefrigeration, which prevent it from being shipped long distances as afresh product. While highly concentrated and dehydrated milk is marketedto a limited extent, whole fresh milk continues to be the form primarilydemanded by the utlimate consumer.

There have been many efforts to dehydrate milk to a highly concentratedor dried form for facilitating its packaging and merchandising, butinsofar as we are aware, no practical way has been found to eliminatethe unpalatableness of highly concentrated or dried milk. Highlyconcentrated or dried milk, when reconstituted by adding 'water,substitutes quite well nutritionally for the fresh product, but thetaste is entirely different and usually considered unpalatable.

Consequently, as a practical matter, the uses of concentrated or driedmilk have been confined to instances in which the taste of the highlyconcentrated or dried milk is sufficiently obliterated to avoidobjection from this standpoint.

The change in taste of milk as it is dehydrated and dried can be causedby a number of factors, though it is usually attributable to somecaramelization of the milk sugars during the dehydrating and dryingprocesses.

The prior art in the field has long recognized the unpalatableness ofhighly concentrated or dried milk after reconstitution, and manyattempts have been made to overcome this problem by employing ways andmeans to reduce the temperatures required to sterilize and concentratethe end product. Generally speaking, these attempts involve the use ofcomplicated de-icing and related techniques to remove water from themilk (see, for instance, Patents Nos. 2,248,634 and 2,343,169), and, ifcomplete drying is desired, a spray drying procedure has been employedwhich necessarily requires involved collection procedures for gatheringthe resulting particles for packaging purposes; see, for instance,Reissue Patent 24,080 and Patent 2,011,558. 7

An early variation in this approach is shown in Patent 523,677, inaccordance with which the product is first concentrated by freezing outwater, then frozen in a thin layer to sterilize it, then flaked off thefreezing surface and thawed, after which it is dried as a liquid undervacuum conditions, then molded into cakes that are again flaked orformed into shavings which are subsequently completely dried by contactwith warm dry carbonic gas, and then powdered, after which, of course,some collection procedure must be provided for packaging the product.

In contrast, our invention takes an entirely new approach. Our newprocess contemplates that the fresh product be first partiallyconcentrated by employing conventional procedures to approximatelyone-third of its volume, after which the resulting concentrate is flashfrozen into a thin sheet that is immediately fragmented into flakes orchips. The resulting frozen flakes or chips are then compacted into acake or block which, in accordance with our above identifiedapplication, is then fully dried under vacuum conditions whilemaintained fully frozen to provide the finished product.

The resulting cake or block is then applied to a suitable containerwhich preferably is proportioned to receive several of the cakes orblocks. The packaged end product is then capable of being merchandisedwithout further handling, and we contemplate that the container used forpackaging purposes may be employed by the ultimate consumer toreconstitute the dried milk product to the dilution desired. Vacuum orinert gas packing (both well known in the art) can be used. The driedcakes could be pulverized where it was desirable to market a powderedproduct.

There are a number of important advantages arising from the practice ofour method of our said patent. In the first place, it will be found thatthe reconstituted product is fully as palatable as the original freshproduct, and this, of course, is of critical importance in this art.

Furthermore, the milk product is handled as a solid cake or block duringthe critical drying and packaging processes or procedures, whicheliminates the need for complex particle gathering techniques andmaterially simplifies the problem of insuring appropriate purificationstandards.

In accordance with the present application, the cake of frozen flakes orchips is not dehydrated, but instead is applied to a suitable container,which preferably is proportioned to receive several of the cakes orblocks, while being maintained under suitable refrigerated conditions,and then the filled containers are merchandized in a manner similar tothe procedures used for frozen fruit uice concentrate and the like.

Therefore, a principal object of our present invention is to provide amethod of packaging concentrated milk which eliminates the taste lossproblems of prior practices.

Another important object of the invention is to provide a method ofpackaging milk in which the milk is provided in frozen form that avoidsany detraction from its palatability.

Further important objects of this invention are to materially simplifyand facilitate milk merchandising procedures and to provide a simplifiedway to freeze milk concentrate and package same.

Other objects of our invention are to provide a simple and economicmethod and apparatus for providing a frozen milk product; to provide afrozen milk product in a shape which lends itself to ready merchandisingprocedures and use by the ultimate consumer; and to provide milkprocessing arrangements which are economical of manufacture, convenientto install, and useable in connection with the processing of a widevariety of grades of milk and milk-like products.

Other objects, uses and advantages will become obvious or be apparentfrom a consideration of the application drawing and the followingdetailed description.

In the drawing:

FIGURE 1 is a diagrammatic perspective view illustrating largely inblock diagram form several of the apparatus components that may beemployed in practicing our invention, arranged to bring out the relationin consecutive order of the initial steps of our method; and

FIGURE 2 is a composite diagrammatic perspective view illustrating moreparticularly one preferred form of the frozen milk product and asuitable merchandising container therefor.

However, it should be distinctly understood that the drawingillustrations are provided primarily to comply with the requirements ofthe patent code, and that those skilled in the art will readily be ableto practice our method using other appropriate apparatus components, andmake modifications in the procedures involved, without departing fromthe scope of the invention.

In practicing our method, fresh whole milk (or homogenized fresh wholemilk) is first dehydrated or concentrated to approximately one-half toone-fourth, say one-third, its original volume by employing conventionalpractices and procedures that avoid caramelization of milk sugars. Forthis purpose, a conventional low temperature vacuum distillationautoclave or drying vessel unit may be employed for both dehydration andsterilizing purposes, and such a unit is generally indicated at inFIGURE 1. The autoclave illustrated is shown as including a suitablecontainer 12 which is heated by electrical heating coil portion 16(connected to a source of electrical power by leads 17) within the tank12, with the raw milk product being supplied through a suitable inlet 18and moisture being drawn off through a suitable conduit 20 by employingan appropriate blower or other conventional apparatus customarilyemployed for this purpose.

When the milk within the autoclave 10- has been brought to approximatelythe concentration indicated, it is discharged through outlet conduit 22by operating suitable valve 24, whereupon the concentrated liquidproceeds to suitable apparatus for freezing it in accordance with ourmethod.

A suitable freezing apparatus is diagrammatically indicated at in FIGURE1, wherein it will be seen that the liquid passes from conduit 22 intoan elongate discharge conduit 32 that is horizontally disposed above anelongate funnel-shaped member 34 positioned directly above a rotatablymounted refrigerated cylinder or drum 36. The liquid discharges fromdischarge conduit 32 through suitable openings 38 into and through theelongate funnel-shaped member 34, which is formed with a narrow elongateoutlet opening 40 that extends parallel to the longitudinal axis ofcylinder or drum 36 and immediately above same. The liquid passesthrough the opening 40 in a thin film and directly onto the exteriorsurface or periphery 42 of drum 36, and drum 36 is refrigeratedsufliciently to immediately freeze (flash freeze, as it is known in theart) the liquid into a thin film, or film like sheet, extendinglengthwise of the periphery 42 (parenthetically, it is here pointed outthat if milk is not rapidly frozen, its fat particles will come out ofemulsification, which would detract from the palatability of the endprodut; consequently, the milk concentrate must be frozen within a timeadequate to prevent the fat particles from coming out of emulsification,which time is well known to those skilled in the art). The cylinder ordrum 36 is rotated in the direction indicated by arrow 44, which appilesthe now frozen milk film against the elongate knife edge 46 of a doctorblade 48 mounted in any suitable manner with its said edge 46 applied inabutting relation with the periphery 42 of the cylinder or drum 36.

This breaks or fragments the frozen milk film into chips or flakes whichthen drop under the action of gravity into a funnel 50 that readies theproduct for the next step in our process. The fragmenting of the filmmay be insured by applying a suitable comminuting arrangement in funnel50.

It may be mentioned at this point that the refrigerated drum or cylinder36 may be of any conventional type and this type of apparatus is wellknown commercially and in the prior art. Of course, the drum or cylinder36 may be mounted for rotation in any suitable manner (not illustrated)and it may be refrigerated in any suitable manner. Conduits 47 and 49are intended to represent any convenient way of getting the refrigerantto and from an appropriate refrigerating system.

It is here pointed out that the primary objective is to flash freeze themilk in as few microseconds as is practical, and that this may beachieved in general by providing the greatest possible exposure of thematerial per mass unit to a heat removing source such as that disclosed.The refrigerated drum arrangement illustrated is one way of achievingthis and it can also be achieved by misting or spraying the milk on flatrefrigerated plates or belt surfaces and providing some suitable way offragmenting and removing the frozen milk for application to a funnel 50or its equivalent. Fast freezing may also be achieved by spraying themilk into a vacuum chamber or onto the surface of a cold liquid, againproviding some way of collecting and fragmenting the frozen product forhandling as herein described.

The frozen milk chips or flakes that fall into the funnel 50 then dropthrough the lower open end 52 of the funnel to appropriate apparatus ormeans for compacting these chips or flakes into a cake or block ofsuitable configuration consistent with the objects of our invention.

In the showing of FIGURE 1, an appropriate cake or block formingapparatus is generally indicated at 60, and is shown as comprising atubular forming cylinder 61 having reciprocably mounted in one end 62thereof an appropriate compacting piston 64 that is actuated through anappropriate piston rod 66 by double acting cylinder 68 that may behydraulically or pneumatically controlled.

Reciprocably mounted in the other end 69 of the cylinder 61 is anejecting piston 70 which is operated through an appropriate piston rod72 by an appropriate type of double acting cylinder 74 that also may behydraulically or pneumatically controlled.

The cylinder 61 and the apparatus 68 and 74 are mounted in any suitablemanner to position the cylinder 61 above a suitable conveyor element 76that may move in the direction indicated by arrow 78. The conveyorelement 76 may be a suitable form of endless belt appropriately trainedin the manner well known to the conveyor art.

The undersurface of the tubular cylinder 61 preferably includes amovable or gate section 82 that may be moved between the open and closedpositions indicated as by employing hydraulically or pneumaticallyoperated cylinder 78 with link 79 being connected between the two bypins 80 and 80a.

The milk flakes or chips leaving the funnel member 50 drop through thefunnel opening 52 into the tubular cylinder 61 onto the movable gatesection 82, and after an appropriate pile is formed, the piston 64 isactuated to move such pile against piston 70, which is held againstmovement, and this compacts the flakes or chips together. This processmay be repeated as required to pack the flakes or chips into a cakehaving a configuration complementing the bore of cylinder 61, and afterthe resulting cake or block achieves the desired size, the movablesection 82 is lowered to open the underside of cylinder 61 and thepiston 70 is moved to eject the resulting cake through such opening ontobelt 76.

The resulting cake is generally indicated at 90 in the lower portion ofFIGURE 1, and after being applied to belt 76, the cakes 90 may beconveyed to a suitable gathering point for application to a dryingapparatus equivalent to that generally indicated by reference numeral100 of FIGURE 2 of our said patent (to which reference may be had for adisclosure of the freeze drying aspects of our method), or, inaccordance with the present invention, for application as a completedproduct to container 140 of FIGURE 2.

Thus, in accordance with the present application, the resultingcompacted cake 90 (which is represented at 90a in FIGURE 2 as a one-halfsize cake) is conveyed to a suitable gathering point for application tocontainers similar in shape to container 140 of FIGURE 2, while beingmaintained under appropriate refrigerated conditions to avoid melting.Container 140 has a shape generally complementing the shape of product90a and is preferably proportioned to hold several of the cakes 90 or90a, and may be a can of any commercial make. The containers 140 arethen merchandised in a manner similar to procedures used for frozenfruit juice concentrate and the like so that the frozen milk cakes willbe available for purchase at any grocery store or supermarket, etc.,that sells goods of this general class.

The ultimate user can thus keep the frozen milk refrigerated in hisrefrigerator or freezer until needed, and, when a can 140 containing thefrozen product is opened, a cake may be removed and placed in a suitablecontainer for melting and adding of water to bring the milk to the usersdesired concentration. Unused cakes 90 or 90a remaining in the can maybe returned to the refrigerator or freezer for storage until needed.

The cakes into which the frozen milk fragments are formed may take anyconvenient shape; for instance, the cakes 90 and 90a may beparallelepiped in configuration, and the parallelepiped configurationand the cylindrical configurations illustrated are preferred becausethey lend themselves so readily to packaging and merchandising purposes.

The methods of our invention may be employed to process not only milkbut other milk-like products such as coffee cream, chocolate milk ordrink, coffee cream substitutes, egg nogg, and skim milk (or powderedskim milk and water) with emulsified added oil or fat, e.g., palm oil,coconut oil, peanut oil, cottonseed oil, and sweet butter. Obviously,milks other than cows milk, such as mothers milk and goat milk, could beprocessed by this method. The method of this invention could be usefulwith many products where the very fast flash freeze in a thin layer(e.g., to avoid emulsion breakdown or other separation of theconstituents) plus eflicient freeze drying in cake form by low costconducted heat would be helpful. Possible examples would be biologicals(such as plasma), vegetable and fruit juices, slurries (such as bananaslurry), mashed potatoes with the milk already in, rubber tree sap(which is an emulsion), and soups. The foregoing description and thedrawings are given merely to explain and illustrate our invention andthe invention is not to be limited thereto, except insofar as theappended claims are so limited, since those skilled in the art who haveour disclosure before them will be able to make modifications andvariations therein without departing from the scope of the invention.

We claim: 1. The method of processing and subsequently packaging a milkproduct to make it suitable for mass merchandising purposes in a mannersimilar to canned frozen juice concentrate and the like, which methodcomprises: concentrating the product to a volume in the range of fromabout /2 to about A. of its original volume,

flash freeze processing the resulting concentrate to provide fullyfrozen solid concentrate fragments having a thickness no greater thanfilm proportions by subjecting the concentrate on a maximum exposure permass unit basis to a heat removing source that effects minimummicro-second solid freezing of the concentrate throughout saidthickness, and then fragmenting said film, compacting the solidconcentrate fragments into cakes, and, while maintaining the cakes intheir fully frozen condition, packaging one or more of the cakes in acontainer proportioned to substantially complement the cakes andsuitable as such for retaining said cakes under ambient air conditionsthat will maintain the solid state of the cakes. 2. The method ofprocessing and subsequently packaging a whole milk product to make wholemilk available in a form suitable for mass merchandising purposes in amanner similar to canned frozen juice concentrate and the like withoutdetracting from the palatableness of the milk, which method comprises:

concentrating the milk to a volume in the range of from about /2 toabout A of its original volume,

flash freeze processing the resulting concentrate to provide fullyfrozen solid concentrate fragments having a thickness no greater thanfilm proportions by subjecting the concentrate on a maximum exposure permass unit basis to a heat removing source that effects minimummicro-second solid freezing of the concentrate throughout saidthickness, and then fragmenting said film,

compacting the solid concentrate fragments into cakes,

and, while maintaining the cakes in their fully frozen condition,packaging one or more of the cakes in a container proportioned tosubstantially complement the cakes and suitable as such for mass merchandising purposes under ambient air conditions that will maintain thesolid state of the cakes,

and retaining the thus packaged cakes under ambient air conditions thatwill maintain the solid state of the cakes.

References Cited UNITED STATES PATENTS 663,502 12/1900 Lain 991922,860,988 11/1958 Keville 99-55 RAYMOND N. JONES, Primary Examiner.

S. E. HEYMAN, Assistant Examiner.

